With continuous development of communications technologies, operators have used optical fibers widely as transmission media in transmission networks to meet people's high requirements for information transmission. An optical fiber transmission network usually includes many spans. Different spans may have different optical fiber types. For example, in a terrestrial wavelength division multiplexing (WDM) transmission system, the most common fibers are a standard single mode fiber (SSMF) and a large effective area fiber (Leaf), which are respectively a G.652 optical fiber and a G.655 optical fiber, and a less common fiber is a dispersion shifted fiber (DSF), which is a G.653 optical fiber. In addition, optical fibers such as a true wave classic (TWC) fiber, a true wave reduced dispersion slope (TWRS) fiber, and a large effective area fiber submarine (LS) are occasionally used. The large effective area fiber submarine is mainly a G.654 optical fiber.
Different types of optical fibers have different core diameters, dispersion coefficients, dispersion slopes, zero-dispersion wavelengths, and the like. As a result, transmission of a WDM system has different nonlinear effects. Nonlinearity is one of the major limitation factors for transmission in the WDM system, and especially, a coherent WDM system. For example, in an 80*100G WDM coherent transmission system, limited by a nonlinear effect, single-wavelength average incident powers are usually: +1 dBm@G.652, −1 dBm@Leaf, and −7 dBm@G.653. As a result, three types of optical fibers support greatly differing transmission distances, which are: 2500 km@G.652, 1600 km@Leaf, and 500 km@G.653. As can be learned, different optical fiber types have significant impact on transmission performance of the WDM system. In phases such as network planning, designing, deployment and commissioning, and operation and maintenance, optical fiber types in all spans need to be accurately known and used as input conditions to ensure working accuracy in these phases.
At present, optical fiber type information is mainly transferred manually in all phases, resulting in low efficiency and occasional errors. Different types of optical fibers have different dispersion coefficients and dispersion slopes. Therefore, a type of an optical fiber may be determined by measuring a dispersion coefficient of the optical fiber. In the prior art, to measure a dispersion coefficient of an optical fiber, staff with meters need to be arranged at both ends of a to-be-tested optical fiber to remove the to-be-tested optical fiber from the WDM system for measurement. As a result, a large amount of time and a large amount of labor are consumed, measurement costs are high, and measurement efficiency is low.